If you're a bull the Federal Reserve has been mixing a cocktail that's blown your socks off.

And with the S&P flirting with all time highs, pros on Wall Street are wondering when the Fed will take the punchbowl off the table. That is, they're wondering when the Fed will begin to wind down its ultra-loose monetary policy.

(In case you're wondering why the punchbowl reference, Jim Cramer said it was first uttered by William McChesney Martin, the longest serving Federal Reserve Chairman, from 1951 to 1970, who said the Fed's job is to take away the punch bowl just as the party gets going.)

The idea of losing the punchbowl is frightening to some pros who aren't sure the stock market can advance without the punch or stimulus as a crutch.

And their worst fears surfaced today after Atlanta Fed president Dennis Lockhart said the Federal Reserve may be able to reduce its bond-buying stimulus plan before the end of this year.

That is, return is so low in the bond market, there are few alternatives but dividend yielding stocks.

If the Fed changes policy and allows rates to rise, even by a small amount, there's fear the stock market could tumble – and tumble badly.

However, Jim Cramer thinks those fears are misguided.

Rob Melnychuk | Brand X Pictures | Getty Images

"I am not worried about the punch bowl being taken away," he said.

"Do you think this Fed, which has aggressively stimulated the economy, is going to take the foot off the gas pedal, now? "Think about it!" Cramer said back in February.

Cramer is convinced the Fed has been too committed to stimulus for too long to withdraw it now and risk consequences. If anything, Cramer thinks the Fed errs on the conservative side which, in this case, would be inflation.